Golf Swing Trainer

ABSTRACT

A trainer is formed of a handle joined to an end of an elongated tubular chamber containing a charge of metal beads. A longitudinal tension rod unites chamber and handle to protect the integrity of the trainer and enable it to be constructed from light weight material such as PVC plastic tubing. The charge of beads weights the trainer to match the feel of a real club. The beads shift in the chamber during a practice swing so that the player sees, feels and hears the shift of the metal beads at appropriate points during the swing, to alert the player when he has swung with proper lag. The beads self-generate a signal by their relative movement in the tube, even without reaching an end of the tube. The player can adjust his swing in increments to alter the point at which the charge of beads shifts in the chamber.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention generally relates to games using a tangible projectile.More specifically, the invention relates to the game of golf and to apractice swingable implement or indicator associated with a swingableimplement. In a further aspect, the invention relates to a device thatis attachable to or integral with a swingable implement and thatincludes a swing or position indicator that provides an audible signalthat is heard by the player.

2. Description of Prior Art

In the game of golf and in several other games that involve swinging animplement to strike a ball, the form of the swing must be correct forthe player to hit the ball with consistency, accuracy and maximumdistance. Consistency is important because golf is a progressive game,where one shot is the basis for the next at each hole, which requiresthat each shot be reasonably good. Accuracy in a golf swing isparticularly challenging because a golf club is relatively long ascompared to other popular swingable implements, such a baseball bats.Further, only the head of the relatively long club can strike the ball.Because the head is at the far end of the club from the player's grip,the head is the most likely portion of a golf club to be in the wrongposition. A proper swing is necessary for the player to accurately andconsistently deliver the club head to the ball's position, in order forthe player to make a good shot. The swing not only must be accurate andconsistent, but it must be delivered with power in order to drive theball a fair distance on drives down the fairway. Accordingly, it is wellrecognized that a golf swing is a demanding motion that requirescoordinated movement of the player's entire body.

Developing a consistently good swing requires extensive practice, sothat the player's body executes a proper swing each time. Players canpractice in many ways. Playing the game of golf is helpful because alltypes of shots are encountered. Practice on a golf driving range ishelpful for honing a particular part of the game. However, much of thetime a player is not at a golf course or driving range but needs topractice his swing, regardless. To meet this need, various swingtrainers are available. A player may wish to practice without regard tothe weather, which results in the player's needing a swing trainer thatis adaptable for indoor practice. An indoor swing trainer can be shorterthan a normal golf club, to better allow indoor use with assurance thatthe shorter swing trainer won't strike walls and ceilings.

In addition to enabling more practice time, a swing trainer can serve asa coach by alerting the player to the correctness of his swing. A goodswing is formed by a series of properly coordinated, sequential motions.The swing starts when the player addresses the ball or the theoreticalposition of the ball, which entails standing in a proper position,facing the ball position, with a golf club held by a proper grip, andwith the club head located slightly behind the ball. The player'sshoulders are aligned parallel with the intended path of the ball. Fromthis starting position, the player executes a backswing in which hebrings the club head in a smooth arc around his trailing shoulder,bringing the club head to a position above and behind the leadingshoulder.

The backswing requires a cocking of the player's wrists as the club headis swung back. Typically, cocking takes place at approximatelyhorizontal club position and is maintained throughout the remainder ofthe backswing. From the backswing stance, the player executes thedownswing, in which the club stays in a cocked position until just afterstriking the ball. However, an important feature of the downswing is tomaintain the wrists in cocked position until the downswing reaches aproper release point at which the wrists start to release, which is justafter striking the ball and while the golfer's body weight is shiftingforward to the leading leg.

“Lag” has been defined as the period of time during a downswing when thewrists remain cocked while hands drop straight down and the body movesslightly open and forward, squaring the club face with the ball;followed by a point when the wrists uncock in the process of strikingthe ball. In abbreviated form, the term “lag” may refer to an element ofa golf swing that manages hand and wrist motions in the describedmanner. Many golfers have difficulty achieving proper lag in theirswings. It would be desirable to have a swing trainer that can assist agolfer in executing a proper swing with “lag” by providing audible,visual and kinesthetic signals when the golfer is properly or improperlyswinging the trainer. The longer the wrists can stay cocked, the moreenergy can be transferred from the club to the ball.

U.S. Pat. No. 5,634,856 to Rainey is an example of a golf swing trainerthat is shorter than a standard length #8 iron golf club. This traineris formed of a tubular body with a grip at one end and a free slidingbearing ball inside the tube. The weight can slide between a plug at thegrip end of the tube and a stop at the end opposite from the grip. Thistrainer operates by selecting the available length of the tube overwhich the bearing ball slides. The length is determined by the transittime for the weight to slide from the plug to the end stop. This traveldistance and weight are coordinated such that the weight strikes againstthe stop when the trainer is swung to the ball impact point of aproperly executed swing. Thus, the length of the tube is selected totime the impact to occur at the precise bottom of a proper swing. Theplayer can evaluate his own swing by judging how closely the audiblesignal sounds relative to the bottom point of the swing. However, thisdevice fails to teach “lag” in the swing. The Rainey trainer uses highmass components, such as a single, large hardened steel slider tosimulate ball impact at the bottom of the downswing. The high mass ofthe slider is insensitive to execution of a proper swing with “lag.”

It is evident that variables in addition to tube length can influencewhen the Rainey weight will strike the end stop. Swing speed stands outas a variable that is likely to produce error. It would be difficult forthe player to calibrate the Rainey trainer without having his ownperfect swing as a reference point. Therefore, a problem with the Raineyapproach is for the player to know when the trainer is properly adjustedto his own swing characteristics.

A further problem with many trainers using a shifting slider is that thegolfer's swing and the trainer's operation may be seeminglyincompatible. This problem might result with a golfer's swing that is sorapid and powerful that the slider in the trainer does not move at all.This problem can be referred to as the power swing deficit. For example,in Rainey the starting position of the slider may be at the distal endof the trainer. A rapid backswing immediately followed by a rapid foreswing may result in the slider being centrifugally trapped at the distalend of the trainer, such that the trainer apparently fails to perform.In such a circumstance, it must be realized that a golf swing can appearto be proper and produce seemingly good strokes. However, in such casesthe golfer is benefitting from his own power as a substitute formaximizing the inherent power that can be released with a better swing.

Golfers practice their swings in many settings. For example, a golfermay practice at home or at a driving range, using his own clubs. Becausegolf clubs tend to be expensive and often are custom fitted to theindividual golfer, golfers often have a strong affinity for using theirown clubs. There can be a resultantly strong temptation for the golferto practice with his own clubs, rather than purchase a trainer. To beaccepted, a trainer needs to show its value in teaching features of thegolf swing that practice with the golfer's own club does not teach.

In convincing a golfer to practice with a trainer, it can be helpful ifthe trainer is less costly than a golf club. Thus, producing a trainerfrom inexpensive materials and commercially available components is anadvantage, as compared to the use of custom roll formed metal parts asfound in Rainey. The use of light weight materials such as plastics inthe body of a trainer is another advantage, which permits the elementsof the trainer that shift position to be a proportionately greater partof the trainer's weight. A trainer also should produce an easilygenerated and detected signal so that, for example, a golfer working tosolve the power swing deficit will begin to receive a corrective signaleven before his new swing is perfected. For this reason, a single highmass slider as found in Rainey may set too high a threshold before thetrainer begins to deliver feedback.

It would be desirable to have a trainer formed of a light weight plasticbody, using a movable charge of small beads instead of a single highmass slider for sending corrective signals.

It would be desirable to have a short swing trainer that delivers asignal indicative of the progress of the swing, rather than just theball impact point. For example, a player should consider wrist action,with cocking and uncocking at suitable times. A player can improve hisswing by learning to employ proper lag throughout his swing, therebymarshalling the power of his swing to maximize at the point of impactwith the ball.

To achieve the foregoing and other objects and in accordance with thepurpose of the present invention, as embodied and broadly describedherein, the method and apparatus of this invention may comprise thefollowing.

SUMMARY OF THE INVENTION

Against the described background, the object of the invention is toprovide a golf swing trainer that teaches the concept of “lag” in a golfswing. This concept is used by many, if not all, professional golfers.

According to the invention, a golf swing trainer is considerably shorterthan a real golf club, where real golf clubs might be as long asforty-eight inches. The trainer is formed of a handle joined to an endof an elongated plastic chamber, which may be transparent. The chambercontains a charge of small beads, BBs, ball bearings, or shot. Thechamber and handle are united by a longitudinal tension rod thatprotects the integrity of the handle and chamber. The tension rod may becalibrated for weight of the charge according to depth measured on therod. Although the trainer is considerably shorter than a real golf club,the charge of beads weights the trainer to a desired degree, such as tomatch the feel of a real club. The weight of a real golf club might betwelve ounces, with considerable variation above or below that weight tosuit the user. However, because the weight of a golf club might beconcentrated at the head, where it is swung on a long shaft, a shortertrainer may require greater weight to produce a similar dynamic feel.The volume of beads can be changed to alter weighting, such as fordifferent golfers, i.e., men, youths and women.

In use, the golfer swings the trainer like a regular club. The beadsself-generate a signal as they move, without the necessity of strikingan end of the chamber. Due to the self-generated signal, a golfer canboth feel and hear any shift in position of the beads at various pointsduring the swing, which tells the golfer when he has swung with properlag. The beads self-generate a signal by their relative movement in thetube, even without reaching an end of the tube. The sound of theshifting charge of beads is an indicator of performance, although thefeel of the beads is a substitute for audible signals among users whocan't hear the moving charge, such as among users having limited hearingability. Through feel and sound, the trainer helps the golfer toproperly move a golf club through backswing and downswing, as well as toset, maintain, and release the golfer's wrists with respect to cockedposition.

The accompanying drawings, which are incorporated in and form a part ofthe specification, illustrate preferred embodiments of the presentinvention, and together with the description, serve to explain theprinciples of the invention. In the drawings:

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is an exploded view of the swing trainer.

FIG. 2 is a side view of the swing trainer, showing the charge of beadsin an unloaded position.

FIG. 3 is a view similar to FIG. 2, showing the charge of beads in atravel position.

FIG. 4 is a view similar to FIG. 2, showing the charge of beads in aloaded position.

FIG. 5 is a first developmental view in the series of FIGS. 5-10,showing a player using the swing trainer in a position addressing theball.

FIG. 6 is a second developmental view of the series of FIGS. 5-10,showing the player using the swing trainer in a position ofmid-backswing and showing the player's wrists having assumed cockedposition.

FIG. 7 is a third developmental view in the series of FIGS. 5-10,showing the player using the swing trainer in a position of fullbackswing with wrists still cocked.

FIG. 8 is a fourth developmental view in the series of FIGS. 5-10,showing the player using the swing trainer in a position of initialdownswing, and showing the wrists still cocked.

FIG. 9 is a fifth developmental view in the series of FIGS. 5-10,showing the player using the swing trainer in a position ofmid-downswing, and showing the wrists still cocked and the charge ofbeads initiating shifting movement toward the distal end of the trainer.

FIG. 10 is a sixth developmental view in the series of FIGS. 5-10,showing the player using the swing trainer in a position of immediatelyafter ball impact, with wrists uncocked and with beads thrown to thedistal end of the chamber with a force that can be felt and heard.

DETAILED DESCRIPTION OF THE INVENTION

The invention is a golf swing trainer 10 that a player may use forpractice to refine his golf swing into a consistently reproducible,power-releasing swing. The trainer 10 is sensitive to aspects of a golfswing that other known trainers do not meaningfully detect and respondto. Trainer 10 issues a visual, audible and haptic signal when theplayer swings with proper lag. In the context of this invention, theterm, “lag,” refers to a period of time in a downswing when cockedwrists and hands drop straight down and the body position shifts toslightly open position and forward to square the club face with theball. At that point the wrists uncock to strike the ball. The longer thewrists can stay cocked, the more energy can be transferred from the clubto the ball. Thus, the trainer 10 teaches delayed uncocking of theplayer's wrists on the downswing. The trainer 10 is designed to teach adownswing where the player's wrists uncock after reaching the impactposition with the ball. Accordingly, both the method and apparatus ofthe invention are directed toward improving a player's golf swing byhelping to manage his swing during the period of lag.

The trainer employs a large number of small weights such as a charge ofbeads or metal spheres that self-generate a training signal as they moveen masse. By such self-generated signal, this charge can respond tostages of such a proper swing in order to guide the golfer to develop aprogressively better swing. It is not necessary for the charge to shiftinto contact with a terminal wall of the trainer in order to provide animpact signal. Many players employ a swing that is a continuous fanmotion that highlights ball impact at the bottom of the swing. Focus onthe ball impact event can encourage the player to try to generate powerby centrifugal swing speed, alone. Often a fan swing fails to observeoptimum wrist action, where uncocking of wrists should not occur toosoon. The swing trainer 10 responds to the timing of when wrists areuncocked to help the player position this event for maximum power in hisswing. The swing trainer might issue additional audible and physicalsignals at other parts of the swing, such as at full backswing and atball impact position, or at any position where the swing is improper. Ofthese signals, the lag signal is the goal for better and consistent golffor the advanced player.

The swing trainer 10 is formed of two elements arranged in longitudinalseries. As best shown in FIG. 1, a handle 12 is positioned at a proximalend or top end of the club, near where the player holds the trainer 10.A tubular weight transfer chamber 14 is positioned at an opposite,distal end of the trainer. The two elements are longitudinally strung ona threaded rod 16 that places both elements in compression, preventsstress failure despite repeated lateral and longitudinal stress imposedby a shifting mass, enables construction using prefabricated plasticparts, ensures against joint failure, and secures the trainer againstimpact failure. The trainer 10 is able to employ a shifting charge ofrelatively high mass, bead-like components, which detects and respondsto subtleties in swing motion, including lag. The response provides asignal to the player when wrists are cocked or uncocked at proper times,thereby helping the player to know when he has achieved correct form andto avoid practicing incorrect form.

The swing trainer has a handle or grip 12. The handle 12 has a core anda wrap that is applied around the core. Together, core and wrap simulatethe grip of a typical golf club. The handle core may be formed of a rodor tube approximately ten inches in length, which is similar to the griplength of a golf club. The preferred material of the trainer grip isthree-quarter inch PVC plastic pipe. This material offers the advantageof being a commodity that is not overly expensive and which is extremelylightweight. The covering wrap is a leather-like material to provide asimilar feel to a regular golf club grip.

The proximal end of the handle 12 is engaged with a proximal end cap 18.The cap 18 is suitably secured to the proximal end of the grip, such asto the core, by a bonding agent or by friction. The cap 18 is aprefabricated plastic pipe cap that can be fastened to the pipe core bysolvent welding or other means. A rod 16 is engaged with, through, or atthe cap 18 in a manner that prevents the cap from lifting away from theend of the rod. For example, a fastener such as a mushroom-headed nut oran acorn nut 20 is threaded to the end of the metal rod 16 outside thecap to serve as a longitudinal retainer and compression element for thecap. Optionally, a relief element is used in association with the nut 20to absorb shock and avoid excess compression on the cap. For example,the relief element may be a washer 22 placed under the nut and formed ofcompressible, resilient material such as rubber or elastomeric material.

An opposite or distal end of the handle 12 is attached in longitudinalalignment with the proximal end of the tubular weight transfer chamber14. A suitable size for a weight transfer chamber 14 is abouttwenty-four inches in length and about one inch in diameter. A suitablejunction connects the relatively larger diameter of the weight transferchamber 14 with the relatively smaller diameter of the handle 12. Anexample of such a suitable junction is a prefabricated, PVC plastic,three-quarter inch to one-inch coupler fitting 24. The proximal end offitting 24 is a junction that receives the distal end of handle 12. Thefitting may be secured to the distal end of the handle core by meanssimilar to those described for securing cap 18 to the proximal end ofhandle 12.

An opposite end of fitting 24 is a junction that receives the proximalend of weight transfer chamber 14. The fitting may be secured to theweight transfer chamber by threads, solvent welding, rod 16, or anyother means, including all methods described for securing cap 18 tohandle 12. The weight transfer chamber 14 may be a tubular plastic pipe,which may be formed of clear plastic to enable visual observation andmeasurement of the tube's contents. Where the tube 14 has a one-inchdiameter, a reduction coupler fitting 24 may be available tointerconnect the tube 14 with the handle core. If such a reductionfitting is not available, it may be fabricated from other standard,prefabricated plastic fittings. For example, a standard fitting size hasa one-inch female slip socket and a one inch female threaded socket.Another standard fitting size has a three-quarter inch female slipsocket and a one-inch male threaded end. The two slip sockets can bejoined to the ends of respective tube 14 and handle 12, while the twothreaded ends can be joined by threaded engagement. Such a fabricatedreduction fitting 24 is desirable because the threaded engagementprovides at least one junction that can be opened for access to theinterior of the tube 14, if required.

A distal end fitting or cap 26 is applied to the distal end of tube 14.The end cap 26 may be secured to the end of tube 14 by any suitablemeans, including any of those described for securing cap 18 to handle12. Metal rod 16 is engaged with, through, or at the cap 26 in a mannerthat prevents cap 26 from separating from the distal end of the metalrod 16. A mushroom headed nut or an acorn nut 28 is threaded to thedistal end of the metal rod 16 outside of cap 26 to serve as alongitudinal retainer for cap 26. At least one of the various suitablefasteners that can be applied to rod 16 can be adjusted to place theside walls of handle 12 and weight transfer chamber 14 in compression.

During assembly of swing trainer 10, a charge 30 of metal beads such asBBs, shot, or steel ball bearings is placed in the weight transferchamber 14 and is sized to only partially fill the chamber so that thecharge can shift from end to end within the chamber and generate anaural signal while shifting. Typically, when compacted at one end of thechamber, a charge will occupy a minor portion of the length of thechamber. As an example, the charge occupies about fifteen to twenty-fivepercent of the chamber length. The size or mass of the charge iscoordinated with the size or musculature of the intended user. Forexample, when the user is a male of normal size, the charge may weighabout 14 ounces and the remainder of the trainer 10 may weigh about 20ounces, producing an overall weight of 34 ounces. The charge 30 iscomposed of a large plurality of bead-like members, which typically willbe steel balls, to enable the charge to self-generate readily perceivedsounds as the charge moves in the weight transfer chamber. As anexample, an ounce of a first brand of commercially obtained 4.5 mm steelBBs contained about forty pieces, while another brand of 4.5 mm BBscontained about one hundred pieces. Members of about 4.5 mm diameter arepreferred because this size performs well and is inexpensive due to theready commercial availability of BBs. These weights suggest that acharge formed of about 4.5 mm diameter balls will contain a hundred ormore members or even a thousand or more. Other types of components maycome in different sizes and different component weights. The chargeshould consist of a large plurality of component pieces, where theminimum is more than a dozen pieces to ensure that a perceptible auralresult is self-generated by interaction between members during movementen masse. Likewise, the charge components are to be large enough ormassive enough to self-generate a perceptible aural result byinteraction between the members during mass movement. At the same time,the components should be small enough to move freely and without jammingbetween the rod 16 and the inner face of the tube 14. In the format ofthe trainer structure, the example weight feels and performs typicallyto certain golf clubs used by men. If the user is smaller, such as afemale or youth, the charge may be smaller in order to correlate theoverall weight with certain golf clubs used by females or youths.

After assembly, it remains possible to change the mass of the charge.Cap 26 or fitting 24 serve as means for selectively sealing and openingan end of tube 14. Either may be threaded or simply attached to tube 14by compression, such that either may be removed to open an end ofchamber 14 even after remaining junctions may optionally have beenpermanently sealed, such as by solvent welding. An advantage of usingrod 16 to capture and secure fittings 24 or 26 to the weight transferchamber is that the fittings 24, 26 need not be permanently attached.Instead, the rod 16 can be released for removing the fittings 24, 26 toopen the chamber and modify the charge of beads. For example, the distalend nut 28 may be removed and cap 26 may be removed, revealing thedistal open end of tube 14 and allowing the addition or removal ofcharge members. Markings or indicia 31 may be incorporated into thestructure of the weight transfer chamber to offer suggested fill levelsof the charge 30 for different users, such as for men, women, orchildren. Suitable locations for such markings 31 are rod 16 or cleartube 14. In this manner, the weight of the trainer 10 can be adjusted tosuit the needs of different users, such as men, women, and children. Themass of the charge in a single trainer may be altered as described, ortrainers may be manufactured containing various selectable charges thatallow user choice.

A typical charge 30 is composed of metal beads having a diameter ofabout three-sixteenths inch or about four millimeters. It is desirablefor the charge 30 to constitute a large portion of the swing trainer'smass, which is aided by the ability to construct the body of the swingtrainer from a light weight substance such as PVC plastic. It isdesirable for the charge of beads or balls 30 to weigh almost as much asthe remainder of the trainer, so that movement of the charge 30 isphysically detectable when the trainer is used. As an example, the massof a typical charge 30 for a swing trainer 10 intended for use by a malemight be 14.2 ounces, while all remaining portions of the swing trainermight have a mass of 20 ounces. This charge 30 weighs about 40% of thetotal, while lighter charges might weigh twenty-five to thirty percentof the weight of the trainer. The use of plastic, or plastic pipe, toform grip and weight chamber contributes to the high ratio of weightlocated in the charge. The relatively large proportion of massattributable to the movable beads self-generates a physical signal whenthe beads do, in fact, move. When the charge is reduced to a smallermass such as 10 ounces, suited for smaller users, the charge remains asubstantial proportion of the overall weight.

In addition to providing a self-generated signal due to shifting mass,the beads self-generate an audible signal from the noise of rubbingagainst one another during any mass movement, even without the beadsfully accumulating at an end of the tube 14. Thus, end caps on the tubeare not essential to performance of the trainer, although theycontribute to the generated signals when struck by the shifting charge.The beads also provide an aural signal by non-movement or partialmovement, which may indicate a condition in the golfer's swing if someother type of signal is appropriate at the point of the signal. In allof these ways, a charge of movable beads generates a greater number andvariety of signals to the player, or self-generates a signal of greatersensitivity to detected conditions, than found with other types ofmoving weights. A further advantage of using rod 16 is that the rod isplaced in tension, which creates a unique aural signal as the beadsinteract with the rod.

The distal end cap 26 closes one end of the trainer while also closingone end of the weight transfer chamber 14. Optionally, the opposite endof the weight transfer chamber can be closed to prevent the charge ofmetal beads from entering the hollow handle 12. The proximal end of theweight transfer chamber can be permanently sealed by applying a suitablysized washer 32 against the proximal end of tube 14 and securing thewasher by a threaded nut 34. A suitable size for the washer 32 matchesthe size of the socket of coupler fitting 24 that receives the proximalend of tube 14.

The handle 12, cap 18, coupler 24, tube 14 and cap 26 are mounted inend-to-end abutment so that these components establish a fixed columnlength that is not subject to further compaction of length. The nuts 20and 28 are applied to the opposite ends of the threaded rod 16 to placethe rod 16 in tension from end-to-end. The resulting structure is highlyresistant to failure due to stress from swinging or due to shifting massin the chamber 14. The stability of the swing trainer 10 is great enoughthat substantially the entire trainer 10, apart from the handle wrap,rod and minor hardware such as washers and nuts, can be manufacturedfrom prefabricated plastic pipe and plastic fittings. Thus, tube 14 maybe formed of one inch PVC plastic pipe. Handle 12 may be formed fromthree-quarters inch plastic pipe. The caps 18 and 26 and coupler 24 maybe plastic fittings sized to fit the respective pipe ends.

The charge 30 of metal beads can move through tube 14 over the fulllength of the tube, which may be about two feet. FIGS. 2-4 show threepossible positions of the ball charge 30 in the tube 14, consideringonly the tube volume. In FIG. 2, the ball charge 30 has moved in thedirection of arrow 36 to be concentrated at the distal end of the tube14 in what can be called an unloaded position. In FIG. 3, the ballcharge 30 is movable in either longitudinal direction within tube 14, inthe direction of either opposed arrow 38 or 40. In FIG. 3, the ballcharge 30 has moved in the direction of arrow 42 to be concentrated atthe proximal end of the tube 14 in what can be called a loaded position.

A normal golf swing often is broken down into five parts: address,backswing, downswing, impact, and follow through. Consideration of thesefive components of a golf swing will demonstrate how to swing withproper lag. With reference to FIGS. 5-10, the swing trainer 10 is usedin a method of practicing a player's 44 golf swing and achieving properlag. The trainer 10 reacts to the dynamics of a golf swing by shiftingthe charge of beads 30 to provide visual, audible and haptic signals.When a player has been provided with a trainer 10, he can learn properlag by following the sequence of motions suggested by FIGS. 5-10.

A practice swing begins in the position of player 44 in FIG. 5,addressing the ball position with a back shoulder 46 and a forwardshoulder 48 approximately aligned with the intended path of the ball.The trainer is in front of player 44 in downward position, as thoughaddressing the ball. The charge of beads 30 is in unloaded position, atthe distal end of chamber 14. The player's wrists 50 are in uncockedposition.

In FIG. 6, the player 44 begins his backswing around his back shoulder46, bringing the trainer through an arc that extends from thetheoretical position of the ball to the backside of the player's head.As the player raises the trainer through about one-half of this arc, hecocks his wrists as shown in FIG. 6. In addition, the charge of beads 30shifts through a travel position to the loaded position at the proximalend of chamber 14. The look, sound and feel of the shifting beadsinforms the player of the transfer of position, by the continuous noiseof the self-generated signal due to shifting beads tumbling over eachother and rolling against the chamber walls and tension rod 16. Theplayer also senses the change in position of the massive charge ofbeads. The backswing continues to the position of FIG. 7, where thedistal end of trainer 10 is approximately behind the player's forwardshoulder 48. The player maintains his cocked wrists 50 as the backswingprogresses.

In FIGS. 8-10, the player executes the beginning of his downswing,approximately following the reverse path of the backswing. In FIG. 8,the player has brought the trainer around his back shoulder 46 withwrists 50 cocked. A key feature of the swing occurs between FIGS. 8 and9. Rather than moving his hands in a free arc, the player drops hishands and wrists, while retaining a cocked position. This dropping ofthe hands and wrists prepares the club to be brought into contact withthe ball with a release of maximum power. In contrast, a player bringinghis hands through a free arc, which would uncock between FIGS. 8 and 9,loses a significant amount of power before reaching the ball position.The mass of small beads in the trainer is especially effective insignaling, by an absence of noise, that the hands are dropping in cockedposition, rather than uncocking, between FIGS. 8 and 9. The presence ofrod 16 in the weight transfer chamber 14 establishes an annularretention volume where the beads are concentrated in the weight transferchamber, such that some beads can fall against the rod while othershifting beads fall against the walls of the chamber 14. The two typesof contact with different materials in different states of tension andcompression establish a sound pattern that effectively signals whenproper hand and wrist motion has been achieved.

In FIG. 9, the player's hands have dropped, and his arms are nearlyfinished with their arc and are at the bottom of the swing. However, theplayer's wrists 50 remain cocked and the trainer is nearly horizontal,suggesting that the trainer still must turn through about 90° of arc.The charge of beads 30 largely remains in loaded position at theproximal end of chamber 14.

FIG. 10 illustrates impact position. The trainer 10 has returned toapproximately vertical position, although the golfer's body is now in aforward shifted position and the trainer is in motion. To reach ballimpact position, the trainer 10 has moved through approximately thefinal quarter arc of the downswing. At impact position, the player'sprimary action is to uncock his wrists 50 as he accompanies theuncocking with a forward shift of body weight to the player's leadingleg. Thus, it is evident that the significant difference between FIGS. 9and 10 is wrist position rather than arm position. Where retainingcocked wrists 50 in FIG. 9 allowed the beads 30 to remain in loadedposition, the uncocking of the wrists 50 in FIG. 10 has caused the beadsto move through travel position and into unloaded position. The beadshave been thrown to the end of the chamber with a force that can be feltand heard while the position of the beads can be seen. Thus, the trainerdelivers its signal in three modes, by being heard, felt, and seen. Thefinal motion caused by uncocking the wrists 50 delivers power to theswing and takes place almost entirely at the ball impact position.

The trainer 10 is configured to resemble a golf club in weight and feel,while being shorter that a typical club in order to achieve severaladvantages. One advantage is that the swing trainer 10 can be used inmany indoor locations where the length of a normal golf club wouldprohibit use. Another advantage is that the swing trainer is moreconvenient to carry and transport than a typical golf club. It canconveniently accompany the player on travels so that he can maintain hisgolf swing on a daily basis. Finally, the length of the trainer iscompatible with the timing of bead travel in the chamber 14.

The foregoing is considered as illustrative only of the principles ofthe invention. Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be regarded as falling within the scope of the invention as definedby the claims that follow.

What is claimed is:
 1. In a golf swing trainer for teaching a player toswing a golf club with proper lag during downswing, wherein the traineris formed of a body having both a proximal hand grip and a distal hollowweight transfer chamber arranged in longitudinal series, the improvementcomprising: a rod longitudinally passing through said hand grip andweight transfer chamber, having a fastener located at least at one ofthe opposite ends of the rod, holding the rod in tension and placing thehand grip and weight transfer chamber in compression; and a chargeformed of a large plurality of bead-like components housed in the weighttransfer chamber, having a component size allowing free movement betweensaid rod and chamber wall, and occupying a minor portion of the chamberlength when compacted at one end of the chamber; whereby the chargeself-generates aural and haptic signals during mass movement within thechamber over distances less than the full length of the chamber.
 2. Thegolf swing trainer of claim 1, wherein said weight transfer chamberfurther comprises an access opening allowing modification of said chargethrough said access opening; and a means for selectively sealing andopening the access opening.
 3. The golf swing trainer of claim 2,wherein said means for selectively sealing and opening the accessopening is a cap located at a longitudinal end of said weight transferchamber.
 4. The golf swing trainer of claim 2, wherein said means forselectively sealing and opening the access opening is a cap located at alongitudinal end of said weight transfer chamber; and said fastener isadjustable on said rod to secure or release said cap with respect to theweight transfer chamber.
 5. The golf swing trainer of claim 1, whereinsaid weight transfer chamber is formed of a clear wall allowing visualperception of said charge, whereby the charge generates visual signalsduring mass movement within the chamber over distances less than thefull length of the chamber.
 6. The golf swing trainer of claim 1,wherein said charge occupies a minor portion of the volume of saidweight transfer chamber, whereby a majority of the volume within theweight transfer chamber is available for the charge to self-generateaural signals during en masse longitudinal movement within the weighttransfer chamber.
 7. The golf swing trainer of claim 6, wherein saidcharge occupies less than twenty-five percent of the volume of saidweight transfer chamber.
 8. The golf swing trainer of claim 1, whereinsaid hand grip and weight transfer chamber are formed of plastic pipe.9. The golf swing trainer of claim 8, wherein said charge comprises atleast twenty-five percent of the weight of the trainer.
 10. The golfswing trainer of claim 1, wherein said large plurality of bead-likecomponents comprises at least one hundred components.
 11. The golf swingtrainer of claim 1, wherein said bead-like components are steel balls.12. The golf swing trainer of claim 1, wherein said bead-like componentsare of a diameter no less than 4 mm.
 13. The golf swing trainer of claim1, wherein said bead-like components are of a diameter no less thanabout 4.5 mm.
 14. The golf swing trainer of claim 1, wherein said chargecomprises at least twenty-five percent of the weight of the trainer. 15.The golf swing trainer of claim 14, wherein said hand grip and weighttransfer chamber are formed of plastic.
 16. The golf swing trainer ofclaim 1, wherein said charge is suitably formulated of sufficient size,shape, mass, and quantity to self-generate audible signals upon movementen masse within said weight transfer chamber.
 17. In a golf swingtrainer for teaching a player to swing a golf club with proper lagduring downswing, wherein the trainer is formed of a body having both aproximal hand grip and a distal hollow weight transfer chamber arrangedin longitudinal series along a common center line, the improvementcomprising: a rod with opposite threaded ends longitudinally passingthrough said hand grip and weight transfer chamber, aligned with saidcommon center line, and with said ends extending beyond the hand gripand weight transfer chamber; a threaded fastener located at each of theopposite ends of the rod, engaging the rod, hand grip, and weighttransfer chamber sufficiently to hold the rod in tension and to placethe hand grip and weight transfer chamber in compression, therebysufficiently stabilizing the assembled hand grip and weight transferchamber to enable the use of plastic pipe to form both the hand grip andweight transfer chamber; and a charge formed of a large plurality ofballs housed in the weight transfer chamber, wherein said balls aresuitably formulated of sufficient size, shape, mass, and quantity toself-generate audible signals upon movement en masse within said weighttransfer chamber.
 18. The golf swing trainer of claim 17, wherein saidcharge is of a volume occupying a minor portion of the chamber lengthwith respect to a positioning compacted at one end of the chamber,whereby the charge self-generates aural and haptic signals during massmovement within the chamber over distances less than the full length ofthe chamber.